There are multiple-user, secure-access applications where electronic devices may be accessible to, and used by, multiple authorized users, but where access must be distinguished for each user. An example of a multiple-user, secure-access, system is a computer terminal in a patient room at a hospital, which may be used by multiple users of multiple categories and authorization levels such as LPNs, RNs, therapists, medical students, and physicians to access and update electronic medical records, but should remain secure from unauthorized users such as hospital visitors. Each category of user may be authorized to access different portions of a medical record and have different levels of authorized access; for example an LPN may be able to read, but not alter, medical orders such as prescription dosage and drug information or dietary restrictions, while being able to enter dates and times each drug was administered to a patient, while a physician is authorized to add and change medical orders including dosages and drugs. It is often desirable to track and log entries according to user; for example, recording the identity of a physician who enters a medical order. In a typical hospital, many multiple-user, secure-access systems are multiple access-point systems, where each individual user may need to access the system from more than one physical location throughout a workday; for example an RN with supervisory responsibility may need to access electronic records through any terminal in an entire emergency-room department.
User logging and user-specific authorization are of use in other fields besides electronic health records. For example, it can be desirable to compartmentalize secret information in a military intelligence or planning environment, or even some industrial research environments, authorizing access to certain data by only particular persons, and other data to other persons, regardless of the terminal or other digital device used to access the data. In order to comply with safety rules, in some industrial and academic laboratory settings it may be desirable to limit access to certain machines to those who have received training specifically for those machines. The wristband herein described may also be used to enable and track usage of copiers, and to unlock security doors only for those having authorized access to certain areas or supply cabinets. Developers of large computer programs also may find it desirable to track access to source code, and to limit write access of specific programmers to those portions of the source code for which they are responsible.
Users who must access or share multiple devices throughout a workday tend to use short, insecure, quickly-entered passwords. They also tend to fail to log out at the end of an interaction with a system, and to use terminals that may still be logged in under another user's identity; occurrences that tend to evade user-specific access and usage restrictions.